Digital subscriber line (DSL) communication is used in a variety of situations at a variety of frequency ranges or bandwidths.
For example, DSL communication between a central office and an end user typically takes place over copper lines. These copper lines can be used simultaneously for analog telephony and DSL communication. One such analog telephony is plain old telephone system (POTS).
Many modern systems now use integrated services digital network (ISDN) communication. ISDN uses a broader frequency range than POTS. When DSL is used together with ISDN, DSL typically uses a frequency range above 138 kHz for communication. In contrast, when DSL is used together with POTS, DSL uses a frequency range of above about 25 kHz.
In another situation, DSL is used without any further services. In this situation, DSL may typically use the whole available bandwidth, as in this situation, voice communication and data communication are typically handled via the same service. In all of these situations, the upper boundary of the DSL frequency range is dependent on the DSL standard used.
For these and other reasons there is a need for the present invention.